﻿<p>An <em>IfcBeam</em> is a horizontal, or nearly horizontal, structural member that is capable of withstanding load primarily by resisting bending. It represents such a member from an architectural point of view. It is not required to be load bearing.</p>

<blockquote class="extDef">NOTE&nbsp; Definition according to ISO 6707-1: 
structural member for carrying load(s) between or beyond points of support, usually narrow in relation to its length and horizontal or nearly so.</blockquote>

<blockquote class="note">NOTE&nbsp; The representation of load-bearing beams in a structural analysis model is provided by subtypes of <em>IfcStructuralMember</em> (with <em>IfcStructuralCurveMember</em> being mostly applicable) as part of an <em>IfcStructuralAnalysisModel</em>.</blockquote>

<blockquote class="note">NOTE&nbsp; For any other longitudinal structural member, not constrained to be predominately horizontal nor vertical, or where this semantic information is irrelevant, the entity <em>IfcMember</em> should be used.</blockquote>

<p>There are two main representations for beam occurrences:</p>
<ul>
 <li><em>IfcBeam</em> with <em>IfcMaterialProfileSetUsage</em> is used for all occurrences of beams, that have a profile defined that is swept along a directrix. The profile might be changed uniformly by a taper definition along the directrix. The profile parameter and its cardinal point of insertion can be fully described by the <em>IfcMaterialProfileSetUsage</em>. These beams are always represented geometricly by an 'Axis' and a 'SweptSolid' or 'AdvancedSweptSolid' shape representation (or by a 'Clipping' geometry based on the swept solid), if a 3D geometric representation is assigned.
<blockquote class="note">NOTE&nbsp; The entity <em>IfcBeamStandardCase</em> has been deprecated, <em>IfcBeam</em> with <em>IfcMaterialProfileSetUsage</em> is used instead.</blockquote>
</li>
 <li><em>IfcBeam</em> without <em>IfcMaterialProfileSetUsage</em> is used for all other occurrences of beams, particularly for beams with non-uniformly changing profile sizes along the sweep, or beams having only 'AdvancedBrep', 'Brep', or 'SurfaceModel' geometry, or if a more parametric representation is not intended.</li>
</ul>

<blockquote class="history">HISTORY&nbsp; New entity in IFC1.0</blockquote>